import winston from "winston";

/**
 * Structured Logging mit Winston
 * Erstellt JSON-Logs für bessere Analyse und Monitoring
 */
export const logger = winston.createLogger({
  level: process.env.LOG_LEVEL || "info",
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.errors({ stack: true }),
    winston.format.json()
  ),
  defaultMeta: {
    service: "graphql-middlelayer",
    environment: process.env.NODE_ENV || "development",
  },
  transports: [
    // Console Output (für Development)
    new winston.transports.Console({
      format: winston.format.combine(
        winston.format.colorize(),
        winston.format.printf(({ timestamp, level, message, ...meta }) => {
          const metaStr = Object.keys(meta).length
            ? JSON.stringify(meta, null, 2)
            : "";
          return `${timestamp} [${level}]: ${message} ${metaStr}`;
        })
      ),
    }),
    // File Output (für Production)
    ...(process.env.NODE_ENV === "production"
      ? [
          new winston.transports.File({
            filename: "logs/error.log",
            level: "error",
          }),
          new winston.transports.File({
            filename: "logs/combined.log",
          }),
        ]
      : []),
  ],
});

// Helper-Funktionen für strukturiertes Logging
export const logQuery = (
  operationName: string,
  variables: any,
  duration: number
) => {
  logger.info("GraphQL Query executed", {
    operation: operationName,
    variables,
    duration: `${duration}ms`,
    type: "query",
  });
};

export const logError = (error: Error, context?: Record<string, any>) => {
  logger.error("Error occurred", {
    error: {
      message: error.message,
      stack: error.stack,
      name: error.name,
    },
    ...context,
    type: "error",
  });
};

export const logCacheHit = (key: string, type: string) => {
  logger.debug("Cache hit", {
    cacheKey: key,
    cacheType: type,
    type: "cache",
  });
};

export const logCacheMiss = (key: string, type: string) => {
  logger.debug("Cache miss", {
    cacheKey: key,
    cacheType: type,
    type: "cache",
  });
};